1193 lines
45 KiB
C#

using UnityEngine;
using System.Collections.Generic;
using Unity.Mathematics;
using Unity.Collections;
using Unity.Burst;
namespace Pathfinding.Graphs.Navmesh {
using System;
using Pathfinding;
using Voxelization.Burst;
using Pathfinding.Util;
using Pathfinding.Jobs;
using Pathfinding.Collections;
using Pathfinding.Pooling;
using UnityEngine.Profiling;
using Unity.Collections.LowLevel.Unsafe;
[BurstCompile]
public class RecastMeshGatherer {
readonly int terrainDownsamplingFactor;
public readonly LayerMask mask;
public readonly List<string> tagMask;
readonly float maxColliderApproximationError;
public readonly Bounds bounds;
public readonly UnityEngine.SceneManagement.Scene scene;
Dictionary<MeshCacheItem, int> cachedMeshes = new Dictionary<MeshCacheItem, int>();
readonly Dictionary<GameObject, TreeInfo> cachedTreePrefabs = new Dictionary<GameObject, TreeInfo>();
readonly List<NativeArray<Vector3> > vertexBuffers;
readonly List<NativeArray<int> > triangleBuffers;
readonly List<Mesh> meshData;
readonly RecastGraph.PerLayerModification[] modificationsByLayer;
readonly RecastGraph.PerLayerModification[] modificationsByLayer2D;
#if UNITY_EDITOR
readonly List<(UnityEngine.Object, Mesh)> meshesUnreadableAtRuntime = new List<(UnityEngine.Object, Mesh)>();
#else
bool anyNonReadableMesh = false;
#endif
List<GatheredMesh> meshes;
List<Material> dummyMaterials = new List<Material>();
public RecastMeshGatherer (UnityEngine.SceneManagement.Scene scene, Bounds bounds, int terrainDownsamplingFactor, LayerMask mask, List<string> tagMask, List<RecastGraph.PerLayerModification> perLayerModifications, float maxColliderApproximationError) {
// Clamp to at least 1 since that's the resolution of the heightmap
terrainDownsamplingFactor = Math.Max(terrainDownsamplingFactor, 1);
this.bounds = bounds;
this.terrainDownsamplingFactor = terrainDownsamplingFactor;
this.mask = mask;
this.tagMask = tagMask ?? new List<string>();
this.maxColliderApproximationError = maxColliderApproximationError;
this.scene = scene;
meshes = ListPool<GatheredMesh>.Claim();
vertexBuffers = ListPool<NativeArray<Vector3> >.Claim();
triangleBuffers = ListPool<NativeArray<int> >.Claim();
cachedMeshes = ObjectPoolSimple<Dictionary<MeshCacheItem, int> >.Claim();
meshData = ListPool<Mesh>.Claim();
modificationsByLayer = RecastGraph.PerLayerModification.ToLayerLookup(perLayerModifications, RecastGraph.PerLayerModification.Default);
// 2D colliders default to being unwalkable
var default2D = RecastGraph.PerLayerModification.Default;
default2D.mode = RecastNavmeshModifier.Mode.UnwalkableSurface;
modificationsByLayer2D = RecastGraph.PerLayerModification.ToLayerLookup(perLayerModifications, default2D);
}
struct TreeInfo {
public List<GatheredMesh> submeshes;
public Vector3 localScale;
public bool supportsRotation;
}
public struct MeshCollection : IArenaDisposable {
List<NativeArray<Vector3> > vertexBuffers;
List<NativeArray<int> > triangleBuffers;
public NativeArray<RasterizationMesh> meshes;
#if UNITY_EDITOR
public List<(UnityEngine.Object, Mesh)> meshesUnreadableAtRuntime;
#endif
public MeshCollection (List<NativeArray<Vector3> > vertexBuffers, List<NativeArray<int> > triangleBuffers, NativeArray<RasterizationMesh> meshes
#if UNITY_EDITOR
, List<(UnityEngine.Object, Mesh)> meshesUnreadableAtRuntime
#endif
) {
this.vertexBuffers = vertexBuffers;
this.triangleBuffers = triangleBuffers;
this.meshes = meshes;
#if UNITY_EDITOR
this.meshesUnreadableAtRuntime = meshesUnreadableAtRuntime;
#endif
}
void IArenaDisposable.DisposeWith (DisposeArena arena) {
for (int i = 0; i < vertexBuffers.Count; i++) {
arena.Add(vertexBuffers[i]);
arena.Add(triangleBuffers[i]);
}
arena.Add(meshes);
}
}
[BurstCompile]
static void CalculateBounds (ref UnsafeSpan<float3> vertices, ref float4x4 localToWorldMatrix, out Bounds bounds) {
if (vertices.Length == 0) {
bounds = new Bounds();
} else {
float3 max = float.NegativeInfinity;
float3 min = float.PositiveInfinity;
for (uint i = 0; i < vertices.Length; i++) {
var v = math.transform(localToWorldMatrix, vertices[i]);
max = math.max(max, v);
min = math.min(min, v);
}
bounds = new Bounds((min+max)*0.5f, max-min);
}
}
public MeshCollection Finalize () {
#if UNITY_EDITOR
// This skips the Mesh.isReadable check
Mesh.MeshDataArray data = UnityEditor.MeshUtility.AcquireReadOnlyMeshData(meshData);
#else
Mesh.MeshDataArray data = Mesh.AcquireReadOnlyMeshData(meshData);
#endif
var meshes = new NativeArray<RasterizationMesh>(this.meshes.Count, Allocator.Persistent);
int meshBufferOffset = vertexBuffers.Count;
Profiler.BeginSample("Copying vertices");
// TODO: We should be able to hold the `data` for the whole scan and not have to copy all vertices/triangles
for (int i = 0; i < data.Length; i++) {
MeshUtility.GetMeshData(data, i, out var verts, out var tris);
vertexBuffers.Add(verts);
triangleBuffers.Add(tris);
}
Profiler.EndSample();
Profiler.BeginSample("Creating RasterizationMeshes");
for (int i = 0; i < meshes.Length; i++) {
var gatheredMesh = this.meshes[i];
int bufferIndex;
if (gatheredMesh.meshDataIndex >= 0) {
bufferIndex = meshBufferOffset + gatheredMesh.meshDataIndex;
} else {
bufferIndex = -(gatheredMesh.meshDataIndex+1);
}
var bounds = gatheredMesh.bounds;
var vertexSpan = vertexBuffers[bufferIndex].Reinterpret<float3>().AsUnsafeReadOnlySpan();
if (bounds == new Bounds()) {
// Recalculate bounding box
float4x4 m = gatheredMesh.matrix;
CalculateBounds(ref vertexSpan, ref m, out bounds);
}
var triangles = triangleBuffers[bufferIndex];
meshes[i] = new RasterizationMesh {
vertices = vertexSpan,
triangles = triangles.AsUnsafeSpan().Slice(gatheredMesh.indexStart, (gatheredMesh.indexEnd != -1 ? gatheredMesh.indexEnd : triangles.Length) - gatheredMesh.indexStart),
area = gatheredMesh.area,
areaIsTag = gatheredMesh.areaIsTag,
bounds = bounds,
matrix = gatheredMesh.matrix,
solid = gatheredMesh.solid,
doubleSided = gatheredMesh.doubleSided,
flatten = gatheredMesh.flatten,
};
}
Profiler.EndSample();
cachedMeshes.Clear();
ObjectPoolSimple<Dictionary<MeshCacheItem, int> >.Release(ref cachedMeshes);
ListPool<GatheredMesh>.Release(ref this.meshes);
data.Dispose();
return new MeshCollection(
vertexBuffers,
triangleBuffers,
meshes
#if UNITY_EDITOR
, this.meshesUnreadableAtRuntime
#endif
);
}
/// <summary>
/// Add vertex and triangle buffers that can later be used to create a <see cref="GatheredMesh"/>.
///
/// The returned index can be used in the <see cref="GatheredMesh.meshDataIndex"/> field of the <see cref="GatheredMesh"/> struct.
///
/// You can use the returned index multiple times with different matrices, to create instances of the same object in multiple locations.
/// </summary>
public int AddMeshBuffers (Vector3[] vertices, int[] triangles) {
return AddMeshBuffers(new NativeArray<Vector3>(vertices, Allocator.Persistent), new NativeArray<int>(triangles, Allocator.Persistent));
}
/// <summary>
/// Add vertex and triangle buffers that can later be used to create a <see cref="GatheredMesh"/>.
///
/// The returned index can be used in the <see cref="GatheredMesh.meshDataIndex"/> field of the <see cref="GatheredMesh"/> struct.
///
/// You can use the returned index multiple times with different matrices, to create instances of the same object in multiple locations.
/// </summary>
public int AddMeshBuffers (NativeArray<Vector3> vertices, NativeArray<int> triangles) {
var meshDataIndex = -vertexBuffers.Count-1;
vertexBuffers.Add(vertices);
triangleBuffers.Add(triangles);
return meshDataIndex;
}
/// <summary>Add a mesh to the list of meshes to rasterize</summary>
public void AddMesh (Renderer renderer, Mesh gatheredMesh) {
if (ConvertMeshToGatheredMesh(renderer, gatheredMesh, out var gm)) {
meshes.Add(gm);
}
}
/// <summary>Add a mesh to the list of meshes to rasterize</summary>
public void AddMesh (GatheredMesh gatheredMesh) {
meshes.Add(gatheredMesh);
}
/// <summary>Holds info about a mesh to be rasterized</summary>
public struct GatheredMesh {
/// <summary>
/// Index in the meshData array.
/// Can be retrieved from the <see cref="RecastMeshGatherer.AddMeshBuffers"/> method.
/// </summary>
public int meshDataIndex;
/// <summary>
/// Area ID of the mesh. 0 means walkable, and -1 indicates that the mesh should be treated as unwalkable.
/// Other positive values indicate a custom area ID which will create a seam in the navmesh.
/// </summary>
public int area;
/// <summary>Start index in the triangle array</summary>
public int indexStart;
/// <summary>End index in the triangle array. -1 indicates the end of the array.</summary>
public int indexEnd;
/// <summary>World bounds of the mesh. Assumed to already be multiplied with the <see cref="matrix"/>.</summary>
public Bounds bounds;
/// <summary>Matrix to transform the vertices by</summary>
public Matrix4x4 matrix;
/// <summary>
/// If true then the mesh will be treated as solid and its interior will be unwalkable.
/// The unwalkable region will be the minimum to maximum y coordinate in each cell.
/// </summary>
public bool solid;
/// <summary>See <see cref="RasterizationMesh.doubleSided"/></summary>
public bool doubleSided;
/// <summary>See <see cref="RasterizationMesh.flatten"/></summary>
public bool flatten;
/// <summary>See <see cref="RasterizationMesh.areaIsTag"/></summary>
public bool areaIsTag;
/// <summary>
/// Recalculate the <see cref="bounds"/> from the vertices.
///
/// The bounds will not be recalculated immediately.
/// </summary>
public void RecalculateBounds () {
// This will cause the bounds to be recalculated later
bounds = new Bounds();
}
public void ApplyNavmeshModifier (RecastNavmeshModifier navmeshModifier) {
area = AreaFromSurfaceMode(navmeshModifier.mode, navmeshModifier.surfaceID);
areaIsTag = navmeshModifier.mode == RecastNavmeshModifier.Mode.WalkableSurfaceWithTag;
solid |= navmeshModifier.solid;
}
public void ApplyLayerModification (RecastGraph.PerLayerModification modification) {
area = AreaFromSurfaceMode(modification.mode, modification.surfaceID);
areaIsTag = modification.mode == RecastNavmeshModifier.Mode.WalkableSurfaceWithTag;
}
}
enum MeshType {
Mesh,
Box,
Capsule,
}
struct MeshCacheItem : IEquatable<MeshCacheItem> {
public MeshType type;
public Mesh mesh;
public int rows;
public int quantizedHeight;
public MeshCacheItem (Mesh mesh) {
type = MeshType.Mesh;
this.mesh = mesh;
rows = 0;
quantizedHeight = 0;
}
public static readonly MeshCacheItem Box = new MeshCacheItem {
type = MeshType.Box,
mesh = null,
rows = 0,
quantizedHeight = 0,
};
public bool Equals (MeshCacheItem other) {
return type == other.type && mesh == other.mesh && rows == other.rows && quantizedHeight == other.quantizedHeight;
}
public override int GetHashCode () {
return (((int)type * 31 ^ (mesh != null ? mesh.GetHashCode() : -1)) * 31 ^ rows) * 31 ^ quantizedHeight;
}
}
bool MeshFilterShouldBeIncluded (MeshFilter filter) {
if (filter.TryGetComponent<Renderer>(out var rend)) {
if (filter.sharedMesh != null && rend.enabled && (((1 << filter.gameObject.layer) & mask) != 0 || (tagMask.Count > 0 && tagMask.Contains(filter.tag)))) {
if (!(filter.TryGetComponent<RecastNavmeshModifier>(out var rmo) && rmo.enabled)) {
return true;
}
}
}
return false;
}
bool ConvertMeshToGatheredMesh (Renderer renderer, Mesh mesh, out GatheredMesh gatheredMesh) {
// Ignore meshes that do not have a Position vertex attribute.
// This can happen for meshes that are empty, i.e. have no vertices at all.
if (!mesh.HasVertexAttribute(UnityEngine.Rendering.VertexAttribute.Position)) {
gatheredMesh = default;
return false;
}
#if !UNITY_EDITOR
if (!mesh.isReadable) {
// Cannot scan this
if (!anyNonReadableMesh) {
Debug.LogError("Some meshes could not be included when scanning the graph because they are marked as not readable. This includes the mesh '" + mesh.name + "'. You need to mark the mesh with read/write enabled in the mesh importer. Alternatively you can only rasterize colliders and not meshes. Mesh Collider meshes still need to be readable.", mesh);
}
anyNonReadableMesh = true;
gatheredMesh = default;
return false;
}
#endif
renderer.GetSharedMaterials(dummyMaterials);
var submeshStart = renderer is MeshRenderer mrend ? mrend.subMeshStartIndex : 0;
var submeshCount = dummyMaterials.Count;
int indexStart = 0;
int indexEnd = -1;
if (submeshStart > 0 || submeshCount < mesh.subMeshCount) {
var a = mesh.GetSubMesh(submeshStart);
var b = mesh.GetSubMesh(submeshStart + submeshCount - 1);
indexStart = a.indexStart;
indexEnd = b.indexStart + b.indexCount;
}
// Check the cache to avoid allocating
// a new array unless necessary
if (!cachedMeshes.TryGetValue(new MeshCacheItem(mesh), out int meshBufferIndex)) {
#if UNITY_EDITOR
if (!mesh.isReadable) meshesUnreadableAtRuntime.Add((renderer, mesh));
#endif
meshBufferIndex = meshData.Count;
meshData.Add(mesh);
cachedMeshes[new MeshCacheItem(mesh)] = meshBufferIndex;
}
gatheredMesh = new GatheredMesh {
meshDataIndex = meshBufferIndex,
bounds = renderer.bounds,
indexStart = indexStart,
indexEnd = indexEnd,
matrix = renderer.localToWorldMatrix,
doubleSided = false,
flatten = false,
};
return true;
}
GatheredMesh? GetColliderMesh (MeshCollider collider, Matrix4x4 localToWorldMatrix) {
if (collider.sharedMesh != null) {
Mesh mesh = collider.sharedMesh;
// Ignore meshes that do not have a Position vertex attribute.
// This can happen for meshes that are empty, i.e. have no vertices at all.
if (!mesh.HasVertexAttribute(UnityEngine.Rendering.VertexAttribute.Position)) {
return null;
}
#if !UNITY_EDITOR
if (!mesh.isReadable) {
// Cannot scan this
if (!anyNonReadableMesh) {
Debug.LogError("Some mesh collider meshes could not be included when scanning the graph because they are marked as not readable. This includes the mesh '" + mesh.name + "'. You need to mark the mesh with read/write enabled in the mesh importer.", mesh);
}
anyNonReadableMesh = true;
return null;
}
#endif
// Check the cache to avoid allocating
// a new array unless necessary
if (!cachedMeshes.TryGetValue(new MeshCacheItem(mesh), out int meshDataIndex)) {
#if UNITY_EDITOR
if (!mesh.isReadable) meshesUnreadableAtRuntime.Add((collider, mesh));
#endif
meshDataIndex = meshData.Count;
meshData.Add(mesh);
cachedMeshes[new MeshCacheItem(mesh)] = meshDataIndex;
}
return new GatheredMesh {
meshDataIndex = meshDataIndex,
bounds = collider.bounds,
areaIsTag = false,
area = 0,
indexStart = 0,
indexEnd = -1,
// Treat the collider as solid iff the collider is convex
solid = collider.convex,
matrix = localToWorldMatrix,
doubleSided = false,
flatten = false,
};
}
return null;
}
public void CollectSceneMeshes () {
if (tagMask.Count > 0 || mask != 0) {
// This is unfortunately the fastest way to find all mesh filters.. and it is not particularly fast.
// Note: We have to sort these because the recast graph is not completely deterministic in terms of ordering of meshes.
// Different ordering can in rare cases lead to different spans being merged which can lead to different navmeshes.
var meshFilters = UnityCompatibility.FindObjectsByTypeSorted<MeshFilter>();
bool containedStatic = false;
for (int i = 0; i < meshFilters.Length; i++) {
MeshFilter filter = meshFilters[i];
if (!MeshFilterShouldBeIncluded(filter)) continue;
// Note, guaranteed to have a renderer as MeshFilterShouldBeIncluded checks for it.
// but it can be either a MeshRenderer or a SkinnedMeshRenderer
filter.TryGetComponent<Renderer>(out var rend);
if (rend.isPartOfStaticBatch) {
// Statically batched meshes cannot be used due to Unity limitations
// log a warning about this
containedStatic = true;
} else {
// Only include it if it intersects with the graph
if (rend.bounds.Intersects(bounds)) {
if (ConvertMeshToGatheredMesh(rend, filter.sharedMesh, out var gatheredMesh)) {
gatheredMesh.ApplyLayerModification(modificationsByLayer[filter.gameObject.layer]);
meshes.Add(gatheredMesh);
}
}
}
}
if (containedStatic) {
Debug.LogWarning("Some meshes were statically batched. These meshes can not be used for navmesh calculation" +
" due to technical constraints.\nDuring runtime scripts cannot access the data of meshes which have been statically batched.\n" +
"One way to solve this problem is to use cached startup (Save & Load tab in the inspector) to only calculate the graph when the game is not playing.");
}
}
}
static int AreaFromSurfaceMode (RecastNavmeshModifier.Mode mode, int surfaceID) {
switch (mode) {
default:
case RecastNavmeshModifier.Mode.UnwalkableSurface:
return -1;
case RecastNavmeshModifier.Mode.WalkableSurface:
return 0;
case RecastNavmeshModifier.Mode.WalkableSurfaceWithSeam:
case RecastNavmeshModifier.Mode.WalkableSurfaceWithTag:
return surfaceID;
}
}
/// <summary>Find all relevant RecastNavmeshModifier components and create ExtraMeshes for them</summary>
public void CollectRecastNavmeshModifiers () {
var buffer = ListPool<RecastNavmeshModifier>.Claim();
// Get all recast navmesh modifiers inside the bounds
RecastNavmeshModifier.GetAllInBounds(buffer, bounds);
// Create an RasterizationMesh object
// for each RecastNavmeshModifier
for (int i = 0; i < buffer.Count; i++) {
AddNavmeshModifier(buffer[i]);
}
ListPool<RecastNavmeshModifier>.Release(ref buffer);
}
void AddNavmeshModifier (RecastNavmeshModifier navmeshModifier) {
if (navmeshModifier.includeInScan == RecastNavmeshModifier.ScanInclusion.AlwaysExclude) return;
if (navmeshModifier.includeInScan == RecastNavmeshModifier.ScanInclusion.Auto && (((mask >> navmeshModifier.gameObject.layer) & 1) == 0 && !tagMask.Contains(navmeshModifier.tag))) return;
navmeshModifier.ResolveMeshSource(out var filter, out var collider, out var collider2D);
if (filter != null) {
// Add based on mesh filter
Mesh mesh = filter.sharedMesh;
if (filter.TryGetComponent<MeshRenderer>(out var rend) && mesh != null) {
if (ConvertMeshToGatheredMesh(rend, filter.sharedMesh, out var gatheredMesh)) {
gatheredMesh.ApplyNavmeshModifier(navmeshModifier);
meshes.Add(gatheredMesh);
}
}
} else if (collider != null) {
// Add based on collider
if (ConvertColliderToGatheredMesh(collider) is GatheredMesh rmesh) {
rmesh.ApplyNavmeshModifier(navmeshModifier);
meshes.Add(rmesh);
}
} else if (collider2D != null) {
// 2D colliders are handled separately
} else {
if (navmeshModifier.geometrySource == RecastNavmeshModifier.GeometrySource.Auto) {
Debug.LogError("Couldn't get geometry source for RecastNavmeshModifier ("+navmeshModifier.gameObject.name +"). It didn't have a collider or MeshFilter+Renderer attached", navmeshModifier.gameObject);
} else {
Debug.LogError("Couldn't get geometry source for RecastNavmeshModifier ("+navmeshModifier.gameObject.name +"). It didn't have a " + navmeshModifier.geometrySource + " attached", navmeshModifier.gameObject);
}
}
}
public void CollectTerrainMeshes (bool rasterizeTrees, float desiredChunkSize) {
// Find all terrains in the scene
var terrains = Terrain.activeTerrains;
if (terrains.Length > 0) {
// Loop through all terrains in the scene
for (int j = 0; j < terrains.Length; j++) {
if (terrains[j].terrainData == null) continue;
Profiler.BeginSample("Generate terrain chunks");
bool anyTerrainChunks = GenerateTerrainChunks(terrains[j], bounds, desiredChunkSize);
Profiler.EndSample();
// Don't rasterize trees if the terrain did not intersect the graph bounds
if (rasterizeTrees && anyTerrainChunks) {
Profiler.BeginSample("Find tree meshes");
// Rasterize all tree colliders on this terrain object
CollectTreeMeshes(terrains[j]);
Profiler.EndSample();
}
}
}
}
static int NonNegativeModulus (int x, int m) {
int r = x%m;
return r < 0 ? r+m : r;
}
/// <summary>Returns ceil(lhs/rhs), i.e lhs/rhs rounded up</summary>
static int CeilDivision (int lhs, int rhs) {
return (lhs + rhs - 1)/rhs;
}
bool GenerateTerrainChunks (Terrain terrain, Bounds bounds, float desiredChunkSize) {
var terrainData = terrain.terrainData;
if (terrainData == null)
throw new ArgumentException("Terrain contains no terrain data");
Vector3 offset = terrain.GetPosition();
var terrainSize = terrainData.size;
Vector3 center = offset + terrainSize * 0.5F;
// Figure out the bounds of the terrain in world space
var terrainBounds = new Bounds(center, terrainSize);
// Only include terrains which intersects the graph
if (!terrainBounds.Intersects(bounds))
return false;
// Original heightmap size
int heightmapWidth = terrainData.heightmapResolution;
int heightmapDepth = terrainData.heightmapResolution;
// Size of a single sample
Vector3 sampleSize = terrainData.heightmapScale;
sampleSize.y = terrainSize.y;
// Make chunks at least 12 quads wide
// since too small chunks just decreases performance due
// to the overhead of checking for bounds and similar things
const int MinChunkSize = 12;
// Find the number of samples along each edge that corresponds to a world size of desiredChunkSize
// Then round up to the nearest multiple of terrainSampleSize
var chunkSizeAlongX = Mathf.CeilToInt(Mathf.Max(desiredChunkSize / (sampleSize.x * terrainDownsamplingFactor), MinChunkSize)) * terrainDownsamplingFactor;
var chunkSizeAlongZ = Mathf.CeilToInt(Mathf.Max(desiredChunkSize / (sampleSize.z * terrainDownsamplingFactor), MinChunkSize)) * terrainDownsamplingFactor;
chunkSizeAlongX = Mathf.Min(chunkSizeAlongX, heightmapWidth);
chunkSizeAlongZ = Mathf.Min(chunkSizeAlongZ, heightmapDepth);
Vector2Int startSample, chunks;
if (float.IsFinite(bounds.size.x)) {
startSample = new Vector2Int(
Mathf.FloorToInt((bounds.min.x - offset.x) / sampleSize.x),
Mathf.FloorToInt((bounds.min.z - offset.z) / sampleSize.z)
);
// Ensure we always start at a multiple of the terrainDownsamplingFactor.
// Otherwise, the generated meshes may not look the same, depending on the original bounds.
// Not rounding would not technically be wrong, but this makes it more predictable.
startSample.x -= NonNegativeModulus(startSample.x, terrainDownsamplingFactor);
startSample.y -= NonNegativeModulus(startSample.y, terrainDownsamplingFactor);
// Figure out which chunks might intersect the bounding box
var worldChunkSizeAlongX = chunkSizeAlongX * sampleSize.x;
var worldChunkSizeAlongZ = chunkSizeAlongZ * sampleSize.z;
chunks = new Vector2Int(
Mathf.CeilToInt((bounds.max.x - offset.x - startSample.x * sampleSize.x) / worldChunkSizeAlongX),
Mathf.CeilToInt((bounds.max.z - offset.z - startSample.y * sampleSize.z) / worldChunkSizeAlongZ)
);
} else {
startSample = new Vector2Int(0, 0);
chunks = new Vector2Int(CeilDivision(heightmapWidth, chunkSizeAlongX), CeilDivision(heightmapDepth, chunkSizeAlongZ));
}
// Figure out which samples we need from the terrain heightmap
var sampleRect = new IntRect(0, 0, chunks.x * chunkSizeAlongX - 1, chunks.y * chunkSizeAlongZ - 1).Offset(startSample);
var allSamples = new IntRect(0, 0, heightmapWidth - 1, heightmapDepth - 1);
// Clamp the samples to the heightmap bounds
sampleRect = IntRect.Intersection(sampleRect, allSamples);
if (!sampleRect.IsValid()) return false;
chunks = new Vector2Int(CeilDivision(sampleRect.Width, chunkSizeAlongX), CeilDivision(sampleRect.Height, chunkSizeAlongZ));
Profiler.BeginSample("Get heightmap data");
float[, ] heights = terrainData.GetHeights(
sampleRect.xmin,
sampleRect.ymin,
sampleRect.Width,
sampleRect.Height
);
bool[, ] holes = terrainData.GetHoles(
sampleRect.xmin,
sampleRect.ymin,
sampleRect.Width - 1,
sampleRect.Height - 1
);
Profiler.EndSample();
unsafe {
var heightsSpan = new UnsafeSpan<float>(heights, out var gcHandle1);
var holesSpan = new UnsafeSpan<bool>(holes, out var gcHandle2);
var chunksOffset = offset + new Vector3(sampleRect.xmin * sampleSize.x, 0, sampleRect.ymin * sampleSize.z);
var chunksMatrix = Matrix4x4.TRS(chunksOffset, Quaternion.identity, sampleSize);
for (int z = 0; z < chunks.y; z++) {
for (int x = 0; x < chunks.x; x++) {
Profiler.BeginSample("Generate chunk");
GenerateHeightmapChunk(
ref heightsSpan,
ref holesSpan,
sampleRect.Width,
sampleRect.Height,
x * chunkSizeAlongX,
z * chunkSizeAlongZ,
chunkSizeAlongX,
chunkSizeAlongZ,
terrainDownsamplingFactor,
out var vertsSpan,
out var trisSpan
);
Profiler.EndSample();
var verts = vertsSpan.MoveToNativeArray(Allocator.Persistent);
var tris = trisSpan.MoveToNativeArray(Allocator.Persistent);
var meshDataIndex = AddMeshBuffers(verts, tris);
var chunk = new GatheredMesh {
meshDataIndex = meshDataIndex,
// An empty bounding box indicates that it should be calculated from the vertices later.
bounds = new Bounds(),
indexStart = 0,
indexEnd = -1,
areaIsTag = false,
area = 0,
solid = false,
matrix = chunksMatrix,
doubleSided = false,
flatten = false,
};
chunk.ApplyLayerModification(modificationsByLayer[terrain.gameObject.layer]);
meshes.Add(chunk);
}
}
UnsafeUtility.ReleaseGCObject(gcHandle1);
UnsafeUtility.ReleaseGCObject(gcHandle2);
}
return true;
}
/// <summary>Generates a terrain chunk mesh</summary>
[BurstCompile]
public static void GenerateHeightmapChunk (ref UnsafeSpan<float> heights, ref UnsafeSpan<bool> holes, int heightmapWidth, int heightmapDepth, int x0, int z0, int width, int depth, int stride, out UnsafeSpan<Vector3> verts, out UnsafeSpan<int> tris) {
// Downsample to a smaller mesh (full resolution will take a long time to rasterize)
// Round up the width to the nearest multiple of terrainSampleSize and then add 1
// (off by one because there are vertices at the edge of the mesh)
int resultWidth = CeilDivision(Mathf.Min(width, heightmapWidth - x0), stride) + 1;
int resultDepth = CeilDivision(Mathf.Min(depth, heightmapDepth - z0), stride) + 1;
// Create a mesh from the heightmap
var numVerts = resultWidth * resultDepth;
var numTris = (resultWidth-1)*(resultDepth-1)*2*3;
verts = new UnsafeSpan<Vector3>(Allocator.Persistent, numVerts);
tris = new UnsafeSpan<int>(Allocator.Persistent, numTris);
// Create lots of vertices
for (int z = 0; z < resultDepth; z++) {
int sampleZ = Math.Min(z0 + z*stride, heightmapDepth-1);
for (int x = 0; x < resultWidth; x++) {
int sampleX = Math.Min(x0 + x*stride, heightmapWidth-1);
verts[z*resultWidth + x] = new Vector3(sampleX, heights[sampleZ*heightmapWidth + sampleX], sampleZ);
}
}
// Create the mesh by creating triangles in a grid like pattern
int triangleIndex = 0;
for (int z = 0; z < resultDepth-1; z++) {
for (int x = 0; x < resultWidth-1; x++) {
// Try to check if the center of the cell is a hole or not.
// Note that the holes array has a size which is 1 less than the heightmap size
int sampleX = Math.Min(x0 + stride/2 + x*stride, heightmapWidth-2);
int sampleZ = Math.Min(z0 + stride/2 + z*stride, heightmapDepth-2);
if (holes[sampleZ*(heightmapWidth-1) + sampleX]) {
// Not a hole, generate a mesh here
tris[triangleIndex] = z*resultWidth + x;
tris[triangleIndex+1] = (z+1)*resultWidth + x+1;
tris[triangleIndex+2] = z*resultWidth + x+1;
triangleIndex += 3;
tris[triangleIndex] = z*resultWidth + x;
tris[triangleIndex+1] = (z+1)*resultWidth + x;
tris[triangleIndex+2] = (z+1)*resultWidth + x+1;
triangleIndex += 3;
}
}
}
tris = tris.Slice(0, triangleIndex);
}
void CollectTreeMeshes (Terrain terrain) {
Profiler.BeginSample("Get tree data from terrain");
TerrainData data = terrain.terrainData;
var treeInstances = data.treeInstances;
var treePrototypes = data.treePrototypes;
var terrainPos = terrain.transform.position;
var terrainSize = data.size;
Profiler.EndSample();
Profiler.BeginSample("Process tree prototypes");
var treeInfos = new TreeInfo[treePrototypes.Length];
for (int i = 0; i < treePrototypes.Length; i++) {
TreePrototype prot = treePrototypes[i];
// Make sure that the tree prefab exists
if (prot.prefab == null) {
continue;
}
if (!cachedTreePrefabs.TryGetValue(prot.prefab, out TreeInfo treeInfo)) {
treeInfo.submeshes = new List<GatheredMesh>();
// The unity terrain system only supports rotation for trees with a LODGroup on the root object.
// Unity still sets the instance.rotation field to values even they are not used, so we need to explicitly check for this.
treeInfo.supportsRotation = prot.prefab.TryGetComponent<LODGroup>(out var dummy);
treeInfo.localScale = prot.prefab.transform.localScale;
var colliders = ListPool<Collider>.Claim();
var rootMatrixInv = prot.prefab.transform.localToWorldMatrix.inverse;
prot.prefab.GetComponentsInChildren(false, colliders);
for (int j = 0; j < colliders.Count; j++) {
// The prefab has a collider, use that instead
var collider = colliders[j];
// Generate a mesh from the collider
if (ConvertColliderToGatheredMesh(collider, rootMatrixInv * collider.transform.localToWorldMatrix) is GatheredMesh mesh) {
// For trees, we only suppport generating a mesh from a collider. So we ignore the navmeshModifier.geometrySource field.
if (collider.gameObject.TryGetComponent<RecastNavmeshModifier>(out var navmeshModifier) && navmeshModifier.enabled) {
if (navmeshModifier.includeInScan == RecastNavmeshModifier.ScanInclusion.AlwaysExclude) continue;
mesh.ApplyNavmeshModifier(navmeshModifier);
} else {
mesh.ApplyLayerModification(modificationsByLayer[collider.gameObject.layer]);
}
// The bounds are incorrectly based on collider.bounds, and may not even be initialized by the physics system.
// It is incorrect because the collider is on the prefab, not on the tree instance
// so we need to recalculate the bounds based on the actual vertex positions
mesh.RecalculateBounds();
treeInfo.submeshes.Add(mesh);
}
}
ListPool<Collider>.Release(ref colliders);
cachedTreePrefabs[prot.prefab] = treeInfo;
}
treeInfos[i] = treeInfo;
}
Profiler.EndSample();
Profiler.BeginSample("Convert trees to meshes");
for (int i = 0; i < treeInstances.Length; i++) {
TreeInstance instance = treeInstances[i];
var treeInfo = treeInfos[instance.prototypeIndex];
if (treeInfo.submeshes == null || treeInfo.submeshes.Count == 0) continue;
var treePosition = terrainPos + Vector3.Scale(instance.position, terrainSize);
var instanceSize = new Vector3(instance.widthScale, instance.heightScale, instance.widthScale);
var prefabScale = Vector3.Scale(instanceSize, treeInfo.localScale);
var rotation = treeInfo.supportsRotation ? Quaternion.AngleAxis(instance.rotation * Mathf.Rad2Deg, Vector3.up) : Quaternion.identity;
var matrix = Matrix4x4.TRS(treePosition, rotation, prefabScale);
for (int j = 0; j < treeInfo.submeshes.Count; j++) {
var item = treeInfo.submeshes[j];
item.matrix = matrix * item.matrix;
meshes.Add(item);
}
}
Profiler.EndSample();
}
bool ShouldIncludeCollider (Collider collider) {
if (!collider.enabled || collider.isTrigger || !collider.bounds.Intersects(bounds) || (collider.TryGetComponent<RecastNavmeshModifier>(out var rmo) && rmo.enabled)) return false;
var go = collider.gameObject;
if (((mask >> go.layer) & 1) != 0) return true;
// Iterate over the tag mask and use CompareTag instead of tagMask.Includes(collider.tag), as this will not allocate.
for (int i = 0; i < tagMask.Count; i++) {
if (go.CompareTag(tagMask[i])) return true;
}
return false;
}
public void CollectColliderMeshes () {
if (tagMask.Count == 0 && mask == 0) return;
var physicsScene = scene.GetPhysicsScene();
// Find all colliders that could possibly be inside the bounds
// TODO: Benchmark?
// Repeatedly do a OverlapBox check and make the buffer larger if it's too small.
int numColliders = 256;
Collider[] colliderBuffer = null;
bool finiteBounds = math.all(math.isfinite(bounds.extents));
if (!finiteBounds) {
colliderBuffer = UnityCompatibility.FindObjectsByTypeSorted<Collider>();
numColliders = colliderBuffer.Length;
} else {
do {
if (colliderBuffer != null) ArrayPool<Collider>.Release(ref colliderBuffer);
colliderBuffer = ArrayPool<Collider>.Claim(numColliders * 4);
numColliders = physicsScene.OverlapBox(bounds.center, bounds.extents, colliderBuffer, Quaternion.identity, ~0, QueryTriggerInteraction.Ignore);
} while (numColliders == colliderBuffer.Length);
}
for (int i = 0; i < numColliders; i++) {
Collider collider = colliderBuffer[i];
if (ShouldIncludeCollider(collider)) {
if (ConvertColliderToGatheredMesh(collider) is GatheredMesh mesh) {
mesh.ApplyLayerModification(modificationsByLayer[collider.gameObject.layer]);
meshes.Add(mesh);
}
}
}
if (finiteBounds) ArrayPool<Collider>.Release(ref colliderBuffer);
}
/// <summary>
/// Box Collider triangle indices can be reused for multiple instances.
/// Warning: This array should never be changed
/// </summary>
private readonly static int[] BoxColliderTris = {
0, 1, 2,
0, 2, 3,
6, 5, 4,
7, 6, 4,
0, 5, 1,
0, 4, 5,
1, 6, 2,
1, 5, 6,
2, 7, 3,
2, 6, 7,
3, 4, 0,
3, 7, 4
};
/// <summary>
/// Box Collider vertices can be reused for multiple instances.
/// Warning: This array should never be changed
/// </summary>
private readonly static Vector3[] BoxColliderVerts = {
new Vector3(-1, -1, -1),
new Vector3(1, -1, -1),
new Vector3(1, -1, 1),
new Vector3(-1, -1, 1),
new Vector3(-1, 1, -1),
new Vector3(1, 1, -1),
new Vector3(1, 1, 1),
new Vector3(-1, 1, 1),
};
/// <summary>
/// Rasterizes a collider to a mesh.
/// This will pass the col.transform.localToWorldMatrix to the other overload of this function.
/// </summary>
GatheredMesh? ConvertColliderToGatheredMesh (Collider col) {
return ConvertColliderToGatheredMesh(col, col.transform.localToWorldMatrix);
}
/// <summary>
/// Rasterizes a collider to a mesh assuming it's vertices should be multiplied with the matrix.
/// Note that the bounds of the returned RasterizationMesh is based on collider.bounds. So you might want to
/// call myExtraMesh.RecalculateBounds on the returned mesh to recalculate it if the collider.bounds would
/// not give the correct value.
/// </summary>
public GatheredMesh? ConvertColliderToGatheredMesh (Collider col, Matrix4x4 localToWorldMatrix) {
if (col is BoxCollider box) {
return RasterizeBoxCollider(box, localToWorldMatrix);
} else if (col is SphereCollider || col is CapsuleCollider) {
var scollider = col as SphereCollider;
var ccollider = col as CapsuleCollider;
float radius = scollider != null ? scollider.radius : ccollider.radius;
float height = scollider != null ? 0 : (ccollider.height*0.5f/radius) - 1;
Quaternion rot = Quaternion.identity;
// Capsule colliders can be aligned along the X, Y or Z axis
if (ccollider != null) rot = Quaternion.Euler(ccollider.direction == 2 ? 90 : 0, 0, ccollider.direction == 0 ? 90 : 0);
Matrix4x4 matrix = Matrix4x4.TRS(scollider != null ? scollider.center : ccollider.center, rot, Vector3.one*radius);
matrix = localToWorldMatrix * matrix;
return RasterizeCapsuleCollider(radius, height, col.bounds, matrix);
} else if (col is MeshCollider collider) {
return GetColliderMesh(collider, localToWorldMatrix);
}
return null;
}
GatheredMesh RasterizeBoxCollider (BoxCollider collider, Matrix4x4 localToWorldMatrix) {
Matrix4x4 matrix = Matrix4x4.TRS(collider.center, Quaternion.identity, collider.size*0.5f);
matrix = localToWorldMatrix * matrix;
if (!cachedMeshes.TryGetValue(MeshCacheItem.Box, out int meshDataIndex)) {
meshDataIndex = AddMeshBuffers(BoxColliderVerts, BoxColliderTris);
cachedMeshes[MeshCacheItem.Box] = meshDataIndex;
}
return new GatheredMesh {
meshDataIndex = meshDataIndex,
bounds = collider.bounds,
indexStart = 0,
indexEnd = -1,
areaIsTag = false,
area = 0,
solid = true,
matrix = matrix,
doubleSided = false,
flatten = false,
};
}
static int CircleSteps (Matrix4x4 matrix, float radius, float maxError) {
// Take the maximum scale factor among the 3 axes.
// If the current matrix has a uniform scale then they are all the same.
var maxScaleFactor = math.sqrt(math.max(math.max(math.lengthsq((Vector3)matrix.GetColumn(0)), math.lengthsq((Vector3)matrix.GetColumn(1))), math.lengthsq((Vector3)matrix.GetColumn(2))));
var realWorldRadius = radius * maxScaleFactor;
var cosAngle = 1 - maxError / realWorldRadius;
int steps = cosAngle < 0 ? 3 : (int)math.ceil(math.PI / math.acos(cosAngle));
return steps;
}
/// <summary>
/// If a circle is approximated by fewer segments, it will be slightly smaller than the original circle.
/// This factor is used to adjust the radius of the circle so that the resulting circle will have roughly the same area as the original circle.
/// </summary>
static float CircleRadiusAdjustmentFactor (int steps) {
return 0.5f * (1 - math.cos(2 * math.PI / steps));
}
GatheredMesh RasterizeCapsuleCollider (float radius, float height, Bounds bounds, Matrix4x4 localToWorldMatrix) {
// Calculate the number of rows to use
int rows = CircleSteps(localToWorldMatrix, radius, maxColliderApproximationError);
int cols = rows;
var cacheItem = new MeshCacheItem {
type = MeshType.Capsule,
mesh = null,
rows = rows,
// Capsules that differ by a very small amount in height will be rasterized in the same way
quantizedHeight = Mathf.RoundToInt(height/maxColliderApproximationError),
};
if (!cachedMeshes.TryGetValue(cacheItem, out var meshDataIndex)) {
// Generate a sphere/capsule mesh
var verts = new NativeArray<Vector3>(rows*cols + 2, Allocator.Persistent);
var tris = new NativeArray<int>(rows*cols*2*3, Allocator.Persistent);
for (int r = 0; r < rows; r++) {
for (int c = 0; c < cols; c++) {
verts[c + r*cols] = new Vector3(Mathf.Cos(c*Mathf.PI*2/cols)*Mathf.Sin((r*Mathf.PI/(rows-1))), Mathf.Cos((r*Mathf.PI/(rows-1))) + (r < rows/2 ? height : -height), Mathf.Sin(c*Mathf.PI*2/cols)*Mathf.Sin((r*Mathf.PI/(rows-1))));
}
}
verts[verts.Length-1] = Vector3.up;
verts[verts.Length-2] = Vector3.down;
int triIndex = 0;
for (int i = 0, j = cols-1; i < cols; j = i++) {
tris[triIndex + 0] = (verts.Length-1);
tris[triIndex + 1] = (0*cols + j);
tris[triIndex + 2] = (0*cols + i);
triIndex += 3;
}
for (int r = 1; r < rows; r++) {
for (int i = 0, j = cols-1; i < cols; j = i++) {
tris[triIndex + 0] = (r*cols + i);
tris[triIndex + 1] = (r*cols + j);
tris[triIndex + 2] = ((r-1)*cols + i);
triIndex += 3;
tris[triIndex + 0] = ((r-1)*cols + j);
tris[triIndex + 1] = ((r-1)*cols + i);
tris[triIndex + 2] = (r*cols + j);
triIndex += 3;
}
}
for (int i = 0, j = cols-1; i < cols; j = i++) {
tris[triIndex + 0] = (verts.Length-2);
tris[triIndex + 1] = ((rows-1)*cols + j);
tris[triIndex + 2] = ((rows-1)*cols + i);
triIndex += 3;
}
UnityEngine.Assertions.Assert.AreEqual(triIndex, tris.Length);
// TOOD: Avoid allocating original C# array
// Store custom vertex buffers as negative indices
meshDataIndex = AddMeshBuffers(verts, tris);
cachedMeshes[cacheItem] = meshDataIndex;
}
return new GatheredMesh {
meshDataIndex = meshDataIndex,
bounds = bounds,
areaIsTag = false,
area = 0,
indexStart = 0,
indexEnd = -1,
solid = true,
matrix = localToWorldMatrix,
doubleSided = false,
flatten = false,
};
}
bool ShouldIncludeCollider2D (Collider2D collider) {
// Note: Some things are already checked, namely that:
// - collider.enabled is true
// - that the bounds intersect (at least approxmately)
// - that the collider is not a trigger
// This is not completely analogous to ShouldIncludeCollider, as this one will
// always include the collider if it has an attached RecastNavmeshModifier, while
// 3D colliders handle RecastNavmeshModifier components separately.
if (((mask >> collider.gameObject.layer) & 1) != 0) return true;
if ((collider.attachedRigidbody as Component ?? collider).TryGetComponent<RecastNavmeshModifier>(out var rmo) && rmo.enabled && rmo.includeInScan == RecastNavmeshModifier.ScanInclusion.AlwaysInclude) return true;
for (int i = 0; i < tagMask.Count; i++) {
if (collider.CompareTag(tagMask[i])) return true;
}
return false;
}
public void Collect2DColliderMeshes () {
if (tagMask.Count == 0 && mask == 0) return;
var physicsScene = scene.GetPhysicsScene2D();
// Find all colliders that could possibly be inside the bounds
// TODO: Benchmark?
int numColliders = 256;
Collider2D[] colliderBuffer = null;
bool finiteBounds = math.isfinite(bounds.extents.x) && math.isfinite(bounds.extents.y);
if (!finiteBounds) {
colliderBuffer = UnityCompatibility.FindObjectsByTypeSorted<Collider2D>();
numColliders = colliderBuffer.Length;
} else {
// Repeatedly do a OverlapArea check and make the buffer larger if it's too small.
var min2D = (Vector2)bounds.min;
var max2D = (Vector2)bounds.max;
var filter = new ContactFilter2D().NoFilter();
// It would be nice to add the layer mask filter here as well,
// but we cannot since a collider may have a RecastNavmeshModifier component
// attached, and in that case we want to include it even if it is on an excluded layer.
// The user may also want to include objects based on tags.
// But we can at least exclude all triggers.
filter.useTriggers = false;
do {
if (colliderBuffer != null) ArrayPool<Collider2D>.Release(ref colliderBuffer);
colliderBuffer = ArrayPool<Collider2D>.Claim(numColliders * 4);
numColliders = physicsScene.OverlapArea(min2D, max2D, filter, colliderBuffer);
} while (numColliders == colliderBuffer.Length);
}
// Filter out colliders that should not be included
for (int i = 0; i < numColliders; i++) {
if (!ShouldIncludeCollider2D(colliderBuffer[i])) colliderBuffer[i] = null;
}
int shapeMeshCount = ColliderMeshBuilder2D.GenerateMeshesFromColliders(colliderBuffer, numColliders, maxColliderApproximationError, out var vertices, out var indices, out var shapeMeshes);
var bufferIndex = AddMeshBuffers(vertices.Reinterpret<Vector3>(), indices);
for (int i = 0; i < shapeMeshCount; i++) {
var shape = shapeMeshes[i];
// Skip if the shape is not inside the bounds.
// This is a more granular check than the one done by the OverlapArea call above,
// since each collider may generate multiple shapes with different bounds.
// This is particularly important for TilemapColliders which may generate a lot of shapes.
if (!bounds.Intersects(shape.bounds)) continue;
var coll = colliderBuffer[shape.tag];
(coll.attachedRigidbody as Component ?? coll).TryGetComponent<RecastNavmeshModifier>(out var navmeshModifier);
var rmesh = new GatheredMesh {
meshDataIndex = bufferIndex,
bounds = shape.bounds,
indexStart = shape.startIndex,
indexEnd = shape.endIndex,
areaIsTag = false,
// Colliders default to being unwalkable
area = -1,
solid = false,
matrix = shape.matrix,
doubleSided = true,
flatten = true,
};
if (navmeshModifier != null) {
if (navmeshModifier.includeInScan == RecastNavmeshModifier.ScanInclusion.AlwaysExclude) continue;
rmesh.ApplyNavmeshModifier(navmeshModifier);
} else {
rmesh.ApplyLayerModification(modificationsByLayer2D[coll.gameObject.layer]);
}
// 2D colliders are never solid
rmesh.solid = false;
meshes.Add(rmesh);
}
if (finiteBounds) ArrayPool<Collider2D>.Release(ref colliderBuffer);
shapeMeshes.Dispose();
}
}
}